The present invention relates to an apparatus and method for cleaning condenser tubes as well as absorber tubes, within a refrigerator of the absorption type or in a compression type refrigerator having a centrifugal or a screw compressor.
In conventional apparatus and methods for cleaning condenser tubes of a refrigerator having a condenser and an evaporator, a cleaning brush is movably mounted within each respective tube that has chambers for capturing the cleaning brush at the opposite ends thereof. Thus the cleaning brush resides in one or the other of these oppositely-disposed chambers during normal operation of the refrigerator. When the tubes are to be cleaned, the cleaning brush is moved through the tube by reversing the flow of fluid such as cooling water therethrough. This is carried out by altering the flow path of the fluid such as cooling water by means of a flow path change valve, so that the inner wall of the tube can be cleaned by the moving cleaning brush.
However, in these conventional cleaning apparatus and methods, a period of time arises in which the amount or the rate of the cooling water flow is slight or non-existent, when the flow of the same is reversed during the cleaning operation. In this period, the pressure within the condenser rises, resulting in a high pressure trip or an overload of a motor depending upon the loading condition, or a surging phenomenon within the centrifugal compressor, together with the occurrence of noises and vibrations, all being disadvantageous effects.
FIG. 1, illustrates conditions during 100% operation of a conventional turbo refrigerator utilizing Freon 11 (trade name) as the refrigerant, when the flow path of the cooling water is changed.
In a conventional refrigerator, a temperature controller for controlling a cooling and heating medium such as a cooling water and a brine within the evaporator is provided, which controls refrigeration capacity depending upon a temperature signal representing a temperature detected within the cooling and heating medium during the refrigeration operation.
In order to eliminate such defects within conventional cleaning apparatus and processes, the timing for changing the flow path of the cooling water is advanced, or actuated when the load is low or the refrigerator is stopped. However, even when the timing for changing the flow path is advanced, the period inevitably arises where the flow amount or rate of the cooling water is slight or non-existent. Therefore, it is extremely difficult, if not impossible, to eliminate the aforementioned disadvantages.
Furthermore, while changing the cooling water flow direction through the condenser tubes during the period of low loading or stands still of the refrigerator might help to alleviate the above-noted problems, the cleaning operation naturally can not then be conducted at fixed intervals or at desired times. Thus, this just results in an undesirably smaller cleaning effect.